This is the Pedi-Cap.





For comparison, here is the Pedi-Cap next to its big brother/sister, the Easy Cap II.





It is tiny. To give you another idea of the size, here it is being used on an itty-bitty baby, who could fit in my hand.



Photo credit


This device is a simple piece of litmus paper. CO₂ (Carbon diOxide) is acidic. In the presence of CO₂, this paper will change from Purple to Yellow. The concentration of CO₂ determines how yellow the paper becomes.^[1]

Some of the problems with this are due to it being nothing more than a piece of litmus paper with a supposedly airtight plastic cover, airtight except for the connections. When litmus paper becomes moist, it does not do what we want it to do in the presence of CO₂. It does not tell us if there is any CO₂ present.

We are looking for the CO₂ because that indicates that the tube is connected with a place that either has a reservoir of CO₂, or to a place that is capable of exchanging CO₂ for O₂ (Oxygen).

If you have been providing mouth-to-mouth ventilation, but have been filling the belly, rather than the lungs, that would be one source of a CO₂ reservoir at the end of the esophagus. After a while, the CO₂ should be removed. In the mean time, you may be misled into leaving the tube in the esophagus and ventilating the stomach. This may not turn out well.

Contraindications
• Not to be used for detection of hypercarbia.
• Not to be used to detect main stem bronchial intubation.
• Not to be used during mouth-to-tube ventilation.
• Should not be used to detect oropharyngeal tube placement.
Standard clinical assessment must be used.^[2]

This is a description of a problem with the Pedi-Cap.

Began ventilating patient with pedi-cap and peds ambubag. Patient began to desaturate immediately. Could not force air thru ambu with Pedicap on. Removed pedi cap and ventilation was accomplished. O₂ sats improved. Manufacturer response (as per reporter) for CO₂ detector, Pedi-Cap "size of the paper in the detector was dimensioned incorrectly causing the device to have a higher flow resistance." Testing other lots to see if same problem exists.^[3]

Let's look at this step-by-step.

Began ventilating patient with pedi-cap and peds ambubag.

No problem, yet.

Patient began to desaturate immediately.

Not a good sign. PALS (Pediatric Advanced Life Support) teaches a 4 step assessment for sudden deterioration of an intubated patient using the mnemonic DOPE (not something to say out loud in front of family). D = Dislodged; O = Obstructed; P = Pneumothorax; E = Equipment failure.

Could not force air thru ambu with Pedicap on.

That would be D for Dislodged. E does not really apply, since that is supposed to be for patients on a ventilator, but use whatever works.

Removed pedi cap and ventilation was accomplished.

Problem solved, but I am guessing that the reason for the assessment of CO₂ has not been addressed.

O2 sats improved.

I'm assuming that the CO₂ was evaluated in some way. Maybe they just kept ventilating and figured that the response to ventilation with bagging was confirmation enough. The immediate improvement in oxygen saturation is unlikely to be a false positive.

Manufacturer response (as per reporter) for CO2 detector, Pedi-Cap "size of the paper in the detector was dimensioned incorrectly causing the device to have a higher flow resistance." Testing other lots to see if same problem exists.



Image modified from the Nellcor product manual.


Nice work by the person ventilating the patient in quickly recognizing a problem and reacting appropriately.

August 14, 2009

Dear Valued Customer,

We are informing you of an urgent voluntary medical device recall regarding the PediCap End-Tidal CO2 Detector (PediCap and PediCap 6).

We have received a customer report in which they experienced difficulty manually ventilating an intubated patient through the PediCap. While we continue to investigate, we believe that a recent modification to the PediCap End-Tidal CO2 Detector may result in increased resistance to airflow through the PediCap. This could result in ineffective ventilation of the patient and/or inadequate detection of CO2 levels, so that the indicator paper will not change color.

Although we have received no reports of patient injury, we have determined that all PediCap and PediCap 6 End-Tidal CO2 Detectors from the lots listed below must be returned. We are requesting your assistance in conducting this activity. Please review your inventory and segregate any product with the affected lot numbers and return affected product according to the directions below^[4]

Likewise, it is nice to see a company responding with a recall, rather than waiting for a patient to be injured. Only one week between the FDA notice and the company recall. While it could be faster, some companies will keep denying problems even after there are a bunch of dead bodies from their product.


Footnotes:


^ ¹ CO₂ detection sheet
Nellcor
Free PDF


^ ² Pediatric End-Tidal CO2 Detector PediCap®
Nellcor
Free PDF


^ ³ FDA Medical Product Safety Report
FDA
08/07/2009
I cannot get Blogger to accept the html for a link to the FDA page. Cut and paste this link:

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/medsun/medsun_details.cfm?ID=%25"-O%3D%25_X%20%0A


^ ⁴ URGENT MEDICAL DEVICE RECALL for PediCap™ End-Tidal CO2 Detectors
Covidien (owner of Nellcor)
August 14, 2009
Free PDF

All necessary information, to contact the company, is in the pdf. Also included are the numbers of all of the lots involved.


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